B. The presence of unconformities
Explanation:
Relation between total pressure and mole fraction is as follows.

where,
= partial pressure of gas 1
= mole fraction of gas 1
= total pressure of the gases
Also, it is known that
= 1
or, 
It is given that total pressure of gas mixture is 0.51 atm and partial pressure of helium is 0.32 atm.
Hence, calculate the mole fraction of helium gas present in the given mixture as follows.

0.32 atm = 
= 0.63
As,
= 1
so, 
= 1 - 0.63
= 0.37
Hence, calculate the partial pressure of Ne as follows.


0.3084 atm = 

= 0.834 atm
Thus, we can conclude that the partial pressure of the Ne in the mixture is 0.834 atm.
Streak. It couldn't be hardness because some minerals are soft and metallic, and some are hard and metallic. Also, it can't be luster, because most gems are minerals, and most luster, but they're not metallic. And it can't be magnetism, because magnetite, the only magnetic mineral, is not really metallic.
Answer:
D.
Explanation:
CH₃C≡ CCH₂CH₂Cl
Since there are 5 carbons so the suffix used is "pent"
There is a triple bond so its alkyne
So the compound becomes 2-pentyne (2 because the triple bond is with the 2nd carbon)
Then,
The functional group of chlorine is attached with 5th carbon So the compound becomes
5-chloro,2-pentyne